Electrical ground fault

I have a circuit which has no power even though the breaker is on. The
power stays off for several months, then suddenly goes back on. Several
months later, it suddenly goes off. I haven't noticed any triggering
events.
The electrician I've been using tells me its a ground fault and can only be
checked when the power is on. He goes from outlet to outlet, fixture to
fixture, testing but never seems to find anything. I'm not even sure what
he's testing! I've forked over a ton of money to this guy and still have a
problem.
Does this sound reasonable, or should I be looking for another electrician?
I wish I could re-wire, but it just isn't in the budget right now!

I would try a different electrician. The cable going to this dead outlet has
to come from somewhere, and depending upon the location of the dead outlet,
such as outside or in a bathroom, it should give a clue to where to look for
the problem. It sounds like a loose connection, but the devil is finding
where

It's not one outlet, it's an entire circuit which (unfortunately) services
PARTS of 3 bedrooms, 3 bathrooms, the den, the upstairs hall, a couple of
basement lights and all of the finished attic. No GFCI on the circuit. My
house is a 200-year old monster which was re-wired - not by us - in the
1970's. I have 28 circuit breakers in the box, but almost half the house is
on this one damn line!
I really would like to know if "ground fault" is a reasonable diagnosis, and
if so, how one would go about finding the problem. I've found it difficult
to get an electrician in for this - all of them here in central NJ are too
busy with new construction to want to be bothered with a nasty problem in a
old house.

Since you have no ground fault circuit interrupters, a ground fault isn't
your problem. If the circuit breaker is tripped and won't reset, it's a
short circuit. If the circuit breaker is on and current is going through it,
you have an open circuit. This problem makes sense in an old house. When
this house was first electrified, they probably had one circuit that went to
a few locations all over the house. Over time people kept tapping that
circuit whenever they wanted to add new outlets and lights, so now you find
90% of the house is on that one circuit. What you really need to have done
is an additional line brought from your panel and feed that part of the
circuit.

The circuit breaker is on, but there is no current anywhere on the line.
One wing of the house was made into an apartment in the '40's, and this was
also on the bad line. We had that rewired to a separate panel about 10
years ago - this on/off problem only happened about 2 years ago. So load
shouldn't be a problem since we have considerably LESS drain on the circuit
now than in the past.

Then measure the voltage at the breaker itself (output screw to neutral
bus). if the breaker is on and there is no voltage, the breaker is bad if
there is voltage, you have an open in the first J box it goes to (unless
someone put a splice in a concieled location, now we would know why not to
do that).
Check that the wire nuts in the first J box on that branch are all in good
tight condition. May need to open them (splice at a nut) to inspect wires
for damage or corrosion. If there is no voltage from hot to neutral or
ground at the first J box then you have the unlikely failure of a wire along
its length (possible Nail intrusion)
If you cannot deduce the location of the cable or first J box on the branch,
you will need to use a signal tracer to follow it inside the wall from the
source at the breaker panel.
Here is one reasonably priced tracer that can be used for LAN, phone and AC
(with hot disconnected at the panel). Others are available optimized for AC
if you look around
http://www.stayonline.com/detail.aspx?IDR41

Not in my opinion. I think it's much more likely that there's an intermittent
connection somewhere. And if you have aluminum wiring, that is _very_
dangerous.

Got any friends who know their way around residential wiring? The solution to
the problem may be nothing more than opening up every junction, switch, and
receptacle box on the circuit, one at a time -- with the circuit OFF -- and
checking manually for loose connections.

Has your electrician pointed out to you where there are GFCI devices
"protecting" that circuit, such as a GFCI breaker in your home's breaker
panel or a GFCI receptical fed by that circuit, which in turn feeds
other devices "downstream" of it?
If he says it is a "ground fault", then he ought to show you how to try
and reset the breaker or receptical when the power "dissappears".
HTH,
Jeff

Reminds me of that TV commercial where the guy is flipping this switch in
his garage and hollering to his wife "is it that one honey" while two doors
away a garage door slams up and down on some old lady's car (presumably
controlled by his switch).
Ground fault means current is traveling from the hot into the ground
conductor, while this may trip a regular breaker and will trip a GFCI
breaker or receptacle, it generally does not cause intermittant operation
with random occurance and long MTBF. A ground fault could be found with the
power off and an ohmmeter between hot and ground. He is limiting his test
method to the one tester he understands (the plug in tester I would guess)
Now if he were looking for an open neutral or hot in a wire nut that
occasionally makes contact when enough vibration gets in the wall, that
would be more reasonable.
Is the whole branch circuit blacked out at once or just a portion of it? It
could take a little time to map out the cables in the walls without seeing
them so one could predict the location of an open. Has he tried the simple,
lets replace the $20 breaker and see if that helps approach.
Seriously, you should only pay his on site estimate fee (usually the first
hour labor or so). If he cannot find and fix a problem, he has not rendered
a service that is billable. If he ultimately fixes it, he is justified to
bill for time spent but if he gives up, the additional time wasted should be
his. Don't pay as you go, he could give up at any time and you will be at
square 1 without a head start.
Find another electrician, not one who works alone or with just 1 or two
partners. Get one of those 1-800-plumber/electrician outfits from the
yellow pages. The pricing is less flexible but in this case that is to your
advantage. Most times they will give you a fixed price quite and there are
several levels of managers to climb if there is a problem, If the
"technician" or Journeyman electrician can't find it Demand they send the
Master out.
If it is working now and you are looking back in time trying to find the
fault, that could be very difficult. Might wait until it blacks out again
to start troubleshooting.

THANK YOU! This is just the advice I was looking for! Which means,
basically, that you've justified my doubts about my electrician, and you've
given me some vocabulary to use with the next one.
My BS radar has been beeping loudly and I've been longing to ask this guy if
my problem will be fixed before his youngest kid is out of college! I'm a
woman who knows enough (after 15 years of renovating a very old house) to
hold my own with most trades, but I have not been able to get a handle on
this problem.

easiest fix is to first split the circuit add a breaker. then find if
the old part or new part fails again.
in any case the time to troubleshoot it is when its failed.
for such a $^%$ makre a drawing of what feeds what starting with the
breaker finding the first outlet in the string. use ohm meter with
power OFF
once you have a complete map, the next time it fails you check each
outlet looking for where its first out
you electrician may believe its a neutral failure, but taking apart
each box is probably the first step

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